Perpetual calendar.



J. P. STIMSON. PERPETUAL CALENDAR. APrLIoATIoN num rms. 1. 190s.

Patented Mar. 23, 1909.

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UNITED STATES PATENT OFFICE.

JOHN F. STIMSON, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO JOHN JAMESKLABER,

OF NEW YORK, N. Y.

IPERPETUAL CALENDAR.

Serial No. 413,802.

To all 'whom it may concern.'

Be it known that I, JOHN F. STIMsoN, a citizen of the United States,residing at 185 Audubon avenue, New York city,New York, have inventedcertain new and useful Imn provements in Perpetual Calendars, of whichthe following is a clear, full, and eXact description.

My invention relates to an improvement in perpetual calendars and to asimplified construction of the same.

My invention will be defined in the claims.

In the preferred embodiment of my invention shown in the drawings,Figure 1 represents a view of the complete calendar; Fig. 2 is alongitudinal section of the same through the center showing a preferredmeans of mounting the disks; and Figs. 3 and 4 are views of the detacheddisks.

A represents the main frame of the calendar, at the lower portionofwhich the two disks B and C of different diameters are concentricallypivoted.

D is a cover card placed on top of the disks B and O and Xedly attachedtothe main card A to form a stationary portion thereof. This card asshown is circular in form but having a concentric portion cut away topartially expose the disks B and C underneath.

In my preferred manner of mounting the disks B and C and cover card D, Ifirmly attach to the main card A, by any suitable means such as glue, abearing post E (see Fig. 2). This post is cylindrical in shape, and asshown is of a slightly less diameter at the lower portion e. The disk Bhas a circular aperture t at its center to fit around the lower end ofthe post e', and disk Chas aV similar aperture c( to fit Varound theupper end of the post. This construction insures a more independentmovement of the disks about their pivots and a more secure attachment,but l do not wish to limit myself to such a particular form. The covercard D is firmly attached to the top of the post in any suitable manner,and thus conceals the pivotal attachment of the disks to present a neatappearance. The disks B and O have suitable finger pieces b2, c2,respectively, byV which they may be manipulated.

At the upper portion of the main card c a space is set 0H in whichdirections or advertising matter may be placed. Below this space ldivide said card intoseven main lon- .son that will acppear hereafter.

gitudinal columns a2 to form a year table. K

In these columns numerals are placed indicating the different years of acentury, zero -to 99, inclusive, and for separating the nu- )year 6, asshown. N umerals indicating leap years are` made to skip a column for areason that will appear hereafter. These leap years are preferablydesignated in some particular manner, as by inclosing them in heavyblack squares, as shown, or printing in color. The cipher isstillfurther designated by an asterisk or the like, to call attention tothe fact that this year is a leap year only when the century is a leapyear. All the numerals having a common left-hand digit are preferablyplaced in transverse alinement to facilitate the discovery of anyparticular year.

The large circular disk B, Fig. 3, l call the century disk. This disk isdivided into sectors b3 in number, preferably a multiple of 7.

The outer ends of this sector b3 are of a width to properly registerwith the lower ends of the columns c2. Any suitable number ofnumeralslindicating centuries are placed in said sectors concentricallyaround the disk in a left-hand consecutive order. For convenience,concentric rings b4 are placed on said disk to separate numerals fallingin the same sector. As all centuries of the new style calendar are notleap years but only those divisible by 400, it is necessary in s acingsaid century numerals around the isks to have due regard for leap yearcenturies and non-leap year centuries. Leap year centuries are placed insectors adjacent to Patented March 23, 1909.

the previous century, while non-leap year centuries are made to skip asector for a rea- Leap year centuries are esignated in any preferredmanner, as by heavily underlining. The numerals indicating the centuriesof the old style calendar in vogue in England up to 1752 have beenplaced in their proper sectors where they overlap the centuries underthe new style calendar instituted by Pope Gre or in 1581. The centuriesof the old sty e ca endar which-overlap the centuries of the new stylecalendar may be printed in color vdividing 29 by 7.

and designatedvv by the words Old style7 printed adjacent thereto. Someeasily distinguished guide mark lf is also placed at any desired pointon the century disk, and other marks i'or convenience may be placed inevery seventh space around said disk. The disk C is also divided intosectors equal in number to the sectors of disk B and adapted to registertherewith. The diiierent .months of the year are placed in said sectorsconcentrically around the disk in a right-hand consecutive order. Thosemonths falling by this method of arrangement in the same sector areseparated from each other by concentric rings c4. For convenience inadjustment of the calendar l prefer to overlap the placing of the monthsso that the entire twelve months will show in any 7 of the sectors, asshown by the drawings. The spacing oi any two consecutive months uponthis disk is determined by the remainder found after dividing the numberof days oi the previous month by the number of days in the week. ThusFebruary is placed in the third space to the right Afrom January,determined by the remainder 3 left from the division of 3l by 7. Inorder to provide for the change of months in leap ears, January andFebruary only are dup icated, the month to be used in a leap year beingplaced one sector to the left oi the regular January and February. Thusin a leap year the distance between the February used and the month ofMarch will be one space, the remainder obtained 'from The remainingmonths are used in the same manner both in leap years and non-leapyears. These leap year months,.January and February, are preferablydistinguished in some particular manner either by heavily underlining orprinting in color. Also in the sectors of disk C separated from themonths by a concentric ring c5 are placed the days oi' the week in theirregular order. The reason for sub-dividing rthe disk in divisions of amulti lle oi 7 is now obvious, as it enables the placing thereon of anequal number of all the days of the week i and in their proper order.

The cover disk D is provided with a monthly date table d, as is usual incalendars,

in a space opposite its cut-away portion, in order to register thecolumns d2 with the outer ends of the sectors of disk C containing thedays of the week. The remaining portion of said cover disk surroundingthis table may be occupied by advertising matter or other directions asto the use of the calendar,

The principle on which my calendar is constructed will be obvious fromthe Vforegoing description in connection with the following briefexplanation.

A slight computation will show `that the day of the week falling on the`same date, for instance January 1st, in two consecutive centurieschan-ges, due te the fact that the number of days in a century is notdivisible evenly by the number of days in a week. Thus 36524 7 equals5217,` with the remainder 5. Two days are lacking for bringing the weekaround to its starting point, and it is convenient to speak of this as,that the dates of successive centuries lose two days of the week. In aleap year century, however, dates lose but one day and the centuries areproperly spaced on the century wheel, as above described, to provide forthis change.

Assuming that the disk C containing the days ofthe week to be carried bythe century disk with the month of January opposite the spot b5 so thatall changes and movements oi the century disk will have reference to themonth of January, then as the century disk is moved to the right tobring successive centuries opposite the 0 year column, the days of theweek will also be moved to the right or backward, bringing the differentdays opposite any particular date column, as for instance the first,which, in the present instance, will indicate the iirst of January.January lst will therefore lose the proper number of days of the weekfor each successive century, in accordance with the spacing of saidcenturies as before described.

It is well known that the day oi the week falling on any particulardate, such as January 1st, will also change for each succeeding yearowing to the division 365 7 equals 52, with the remainder 1. lt is convenient to speak of this as the dates of each successive year gain aday. lt should be kept in mind, however, that in the year following theleap year the dates gain two days. Assuming that the days are stillcarried bythe century disk, then as the disk is turned to the left tobring any particular century, for example 1900, opposite successiveyears, the days of the week will move forward past the first datecolumn, referring to January ist. Thus January 1st will gain a day ofthe week for each ordinary year, and two days for each leap year. As thedates in January and February in a leap year should gain only one day,while the remaining months should gain two days, the reason for myduplication of the months January and February on disk )C is nowapparent. lf'ilhen the century disk is moved ahead tivo spaces v incoming opposite a leap year column, the

days carried thereby will be moved two spaces, but the furtheradjustment of the disk C to bring the leap year January opposite .spotb5 results in merely changing the day of the week one day ahead.

By the above explanation it is clear that if the days of the week werecarried by the century disk, the day registering with the iirst ofJanuary would be properly changed by the manipulation of the centurydisk with reference to the year table. As the first day of eachsucceeding month after January changes, the day of Vtheweek oppositevthe first date column must be still further changed for each month. Thisis accomplished by having the days carried on a separate disk from thecentury disk, and sliding this second disk C in relation to the centurydisk different distances each month. M preferred method of adjustingthis second disk relative to the. century disk is to place the monthsthereon and space them as previously described. The months may be thusmoved past any designated point, as b5, on the century disk to registerthe different months therewith which obviously changes the days of theweek corresponding to the number of spaces between the diHerent months.

The directions for using my calendar are as follows. Bring the centuryin the outer disk to the bottom of the column containing the year. Placethe month opposite the black space on the century disk. The calendar isthen set for the month To find the year in any century above 2400,divide the century desired by 400, and if there be no remainder, use thecentury 2000 of my disk. If there be a remainder of 100, use 2100 as thecentury. lf there be a remainder of 200 use 2200. If there be aremainder of 300 use 2300. Thus for any year in the century 2900 400equals 7 with the remainder of 100. Therefore use 2100.

I understand that many changes may be made in the construction shown inthe drawings without departing from the spirit of my invention asdeiined in the claims, and I therefore do not wish my claims to belimited to the particular embodiment here shown.

What I claim is:

1. A perpetual calendar comprising a main card having a year tablethereon containing the years zero to 99 inclusive, a card relativelymovable thereto and having representations of centuries adjacent saidyear table, said movable card adapted to register the several centurieswith the different years, a stationary portion of said main card havinga monthly date table thereon including the numerals 1 to 31' inclusive,a second movable card having thereon the days of the week arrangedadjacent said monthly date table of said stationary portion to registertherewith,

and also having the months ofthe year thereon arranged adjacent saidErst movable card.

2. A perpetual calendar comprising a main card having a year tablethereon made u of numerals Zero to 99 inclusive, arrange in columns, acentury card relatively movable to said maincard and havingrepresentations of centuries arranged in spaces adjacent to said yeartable, a stationary portion having a monthly date table thereon made upof nuthe years zero to 99 inclusive,

n) La merals 1 to 31 inclusive arranged in columns, a second movablecard having the days of the week arranged in spaces adapted to registerwith said monthly date column, said second movable card also having themonths of the year arranged in spaces adjacent said century card, andadapted to register said months With any desired point of said centurycard. 3. A perpetual calendar comprising a main card having a year tablethereon containing a centurydisk plivotally mounted on said main cardand aving representations of centuries thereon adjacent said year table,said disk adapted to be rotated to register the several centuries withthe different years of the year table, a

` card portion fixed to said main card having a monthly date tablethereon containing the numerals 1 to 31 inclusive, a second diskpivotally mounted on said main card having the days of the Week thereonarranged adjacent to said monthly date table and adapted to registertherewith, said disk also having thereon the months of the year arrangedadjacent to said century disk, and adapted to register said months withany desired point of said century disk.

4. A perpetual calendar comprising a main card having a year tablethereon made up of numerals zero to 99 inclusive arranged in columns, acentury disk pivotally mounted on said main card and havingrepresentations of centuries thereon arranged concentrically around saiddisk in sectors thereof, a stationary card portion iXed to said maincard having a monthly date table thereon made up of numerals 1 to 31inclusive arranged in columns, a second pivoted disk having the days ofthe week and also the months of the year arranged concentrically aroundsaid disk in sectors thereof.

5. A perpetual calendar comprising a main card having a year tablethereon made u of numerals Zero to 99 inclusive arranged) in columns, acentury disk pivoted on said main card and having representations ofcenturies arranged concentrically around the outer portion of said diskin sectors and adapted to register with said year columns, a second disksmaller in diameter than said century disk pivoted concentricallytherewith, said second disk having the months of the year arrangedconcentrically around the outer portion thereof in sectors adjacent saidcentury disk, a card member fixed to said main card and having a monthlydate table thereon made up of numerals 1 to 31 inclusive arranged incolumns, said second disk having the days of the week arrangedconcentrically around the inner portion thereof in sectors and adaptedto register with said monthly date columns.

6. A perpetual calendar comprising a main card having a year tablethereon containing the years 0 to 99 inclusive, a century card movablerelatively thereto and having repre.- sentations of centuries thereonand means for registering said centuries with the differs ent years, aeard member having a monthly date table thereon containing the numerals1 to 31 arranged in columns, a separate eard member having the days ofthe Week thereon and being relatively adjustable to the eard having themonthly date columns thereon, one of said last-named card members havingthe different months of the year thereon adliaeent to said century eardand means for ad justing said monthly representations relatively to saidcentury card to brin the prouer days of the Week in registry with t iemont ily date columns.

Signed at New York eity this 30th day of January 1908.

i JOHN F. STIMSON.

Witnesses CHESTER T. NEAL, BEATRICE Mmvrs.

